Global Patent Index - EP 0903664 A3

EP 0903664 A3 20000202 - Floating-point processor with operand-format precision greater than execution precision

Title (en)

Floating-point processor with operand-format precision greater than execution precision

Title (de)

Gleitkommaprozessor mit einer Operandenformatgenauigkeit grösser als die Ausführungsgenauigkeit

Title (fr)

Processeur à virgule flottante ayant une précision de format d'opérande supérieure à la précision d'exécution

Publication

EP 0903664 A3 20000202 (EN)

Application

EP 98117383 A 19980914

Priority

US 93444997 A 19970919

Abstract (en)

[origin: EP0903664A2] A floating-point processor (AP1) nominally capable of single and double, but not extended, precision execution stores operands in extended-precision format. A format converter (FMT) converts single and double precision source values to extended-precision format. Trap logic (TPL) checks the apparent precision of the extended-precision operands and the requested result precision to determine whether the floating-point processor (AP1) can execute the requested operation and yield the appropriate result. If the maximum of the requested precision and the maximum apparent precision of the operands is single or double, the requested operation is executed in hardware (EXU). Otherwise, a trap is issued to call an extended precision floating-point subroutine (SUB). This approach augments the class of operations that can be handled in hardware by a double-precision floating-point processor (AP1), and thus improves the floating-point computational throughput of an incorporating computer system. <IMAGE>

IPC 1-7

G06F 7/48

IPC 8 full level

G06F 7/57 (2006.01); G06F 9/30 (2006.01); G06F 9/38 (2006.01)

CPC (source: EP US)

G06F 7/483 (2013.01 - EP US); G06F 9/3013 (2013.01 - EP US); G06F 9/3861 (2013.01 - EP US); G06F 9/3877 (2013.01 - EP US); G06F 7/49942 (2013.01 - EP US); G06F 2207/382 (2013.01 - EP US)

Citation (search report)

  • [YD] WO 9531767 A1 19951123 - VLSI TECHNOLOGY INC [US]
  • [A] US 5630160 A 19970513 - SIMPSON RICHARD [GB], et al
  • [Y] DARLEY M ET AL: "THE TMS390C602A FLOATING-POINT COPROCESSOR FOR SPARC SYSTEMS", IEEE MICRO, vol. 10, no. 3, June 1990 (1990-06-01), pages 36-46, XP000179277, ISSN: 0272-1732

Designated contracting state (EPC)

AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

DOCDB simple family (publication)

EP 0903664 A2 19990324; EP 0903664 A3 20000202; US 6029243 A 20000222

DOCDB simple family (application)

EP 98117383 A 19980914; US 93444997 A 19970919